God Helmet Experiments use Blind Protocols and Placebo Controls – A Blog By Dr. M.A. Persinger

God_helmetOur God Helmet experiments employ double-blind conditions and placebo protocols – a Blog by Dr. Michael A. Persinger.

Our Critics are mistaken when they claim we do not use proper controls.  We are committed to the scientific method, especially in laboratory experiments, including subject blindness, experimenter blindness, control groups, and blindness by those who analyse our data.

Question:  What are your standard double-blind and placebo controlled protocols?

Answer: Expectancy and confirmation bias are always important variables when human beings are measuring or being measured. Most of our major experiments over the last three decades with the sensed presence were double blind.  For a placebo, we use a “sham” or absent magnetic field, which we create by disconnecting the solenoids (magnetic coils) from the signal source.  We also exploit all ways and means for ensuring that our subjects are not given any suggestions as to the purpose of the experiment.

Subject Expectations

The subjects volunteered for a relaxation study and were told (via the consent form) they might be exposed to a weak magnetic field. Four to six weeks prior to their participation, the subjects had completed intake questionnaires.  Some critics have mistakenly said that our questionnaires (which asked about some spiritual and otherworldly experiences and beliefs) were administered immediately before the experimental sessions, and that this introduced inadvertent suggestions. In fact, our standard procedure is to separate the questionnaires from the sessions by an average of a month.  They are eventually invited to participate in a “Relaxation Experiment”, so they are unaware that the questionnaires given previously have any relation to the experiment.  The subjects are kept in the experimentally blind condition.  They are not influenced by expectations when coming into our lab.  The lab itself looks like a busy workplace, and is not decorated with religious or spiritual images.

Blind Protocols

The experimenter, usually an undergraduate or graduate student, who runs the experiment is not aware of the true hypothesis or mechanism.

One summary of our work with the sensed presence is our publication, “The sensed presence within experimental settings: implications for the male and female concept of self” The Journal of Psychology, 2003, 137, 5-16. link

Here is a very brief summary of that experiment, with its 50 male and 50 female subjects.

In this study, we used a signal derived from burst-firing in the amygdala, applying it over the temporal lobes via a set of four solenoids over each temporal lobe.  We rotated the signal by turning them on and off in sequence.  All of this was built into the hardware (The God Helmet) or coded into the software that drives it, written by Stanley Koren.  We applied the signal for 10 minutes, gave it a 5 minute break, and applied it for another 10 minutes.  This was done to avoid habituation.

We observed double-blind conditions (access the research report):

“All participants were tested by experimenters who were not familiar with the purpose of the experiment.”

“The participants were told that the experiment was concerned with relaxation.”

Note that in some experiments, subjects were told that the experiment concerned memory.  The relaxation and memory suggestions kept the subject in an experimentally blind condition.

The experimenter ran different patterns of magnetic fields created by Professor Stan Koren and me.  Once the results were collected they were analyzed routinely by SPSS  (statistical analysis) software.

Women reported more frequent experiences of a sensed presence than men did , and men were more likely than women to consider these experiences as “intrusions” from extrapersonal or ego-alien sources. Both effects were predicted by one of our hypotheses (vectoral hemisphericity) and the known neurologically-based cognitive differences between right-handed men and right-handed women.

The point here is that we do in fact use double-blind conditions, and claims to the contrary are simply not true.  Other examples, referenced here, include Richards (1992) Persinger (1994), Healey (1996), Persinger (1999), Persinger, (2002) Booth (2005), Tiller (2002), Corradini, (2014).  I have emphasized this in my response to Pehr Granqvist (who made critical technical errors with our equipment, and alleged that our results were due to improper blinding and subject suggestibility), as follows:

“In all of our major studies, involving more than 400 subjects, during the last 20 years the subjects were not aware of their experimental conditions and experimenters were not familiar with the hypotheses being tested or both were not aware of the experimental condition. Subjects had volunteered for “memory” or “relaxation” studies and were randomly or serially allocated to conditions. The “sensed presence” issue was never discussed. The person generating the hypothesis never had direct contact with the subjects.” (Persinger, 2005)

Regrettably, online critics often fail to include this critical reply to Dr. Granqvist.

Let me underscore that we have applied double-blind protocols in our “sensed presence” studies, (to make the differences in stimulation explicit) by quoting another of our papers:

“Under double blind conditions, the subjects who were exposed to the burst-firing pattern presented over both hemispheres or the right hemisphere reported more sensed presences than those exposed to the sham-field [control] or to left hemispheric presentations. Subjects in the latter condition reported fewer sensed presences than the sham-field controls. (Booth, 2005 B)”

Here, stimulation of the right hemisphere is compared to both stimulation of the left, and to controls.  This method allows greater certainty for our results.

Moreover, we often employ “blind” analysis of EEG and QEEG data, in which the person carrying out the analysis does not know what hypothesis the data is intended to study (Makarec, 1990).

In our rat studies, we also carry out blind analysis of rat brain sections, in which the investigator does not know which brain regions may have been affected by a procedure, or the magnitude of the differences predicted between the rat brains used in the study and those which were not (Fournier, 2012). In rat studies investigating differences in rat behavior following stimulation with magnetic signals, the experimenter observing their behavior is kept blind to the experimental condition (Whissell, 2007, McKay, 2004, Bureau, 1994, Babik, 1992).  Our examination of microscope slides from rat subjects and controls is also done under blind conditions (Cook, 1999). We have also carried out similar procedures with worm (planarium – Dugesia sp.) studies (Mulligan, 2012).

” …a total of 10 undergraduate students participated in measuring the worms’ activity; the students were unaware of the experimental conditions, that is, the study was completely “blind”.”

When we analyze the congruence between intuitively-derived narratives from individuals with exceptional cognitive skills and actual information, we use groups of student “raters” who compare the two data sets, and rate the degree of congruence.  All raters are “blind” in that they don’t know anything about the circumstances under which the narratives were derived, or the overall purpose of the experiment (Hunter, 2010).  We also employed the same technique to assess the accuracy of remote viewing by the artist Ingo Swann using graphic images he sketched during remote viewing sessions, augmented by our “Octopus” apparatus (Persinger, 2002, B).  In a related case history, we attempted to interpolate a specific image from a collection of art prints into the dreams of another.  The “agent”, who repeatedly viewed a randomly-chosen (based on dice throws) art image, was the only one who knew which image was being used.

“The interviews were conducted double blind; neither the percipient nor the experimenters knew the identity of the target or the pool of art prints from which the target had been randomly selected.”

The results demonstrated that greater accuracy was associated with lower geomagnetic activity.

Placebo Controlled, Double-Blind Studies.

Our placebo controls are created by using inert electromagnets (solenoids).  These are not attached to the signal source.  The experimental procedures are identical in all other respects.  We also use our sham fields in studies in conjunction with double-blind conditions.  Here are a few examples:

  • Corradini’s (2014) study facilitating declarative memory
  • Fournier’s (2012) experiment with prenatal rat hippocampus stimulation
  • Mulligan’s (2012) study with planaria.
  • Whissell’s (2007) experiment on the interactions of nitric oxide and seven hertz magnetic fields.
  • Booth’s (2005) sensed presence study.
  • My own study on increased alpha activity from the left hemisphere with stimulation with our burst-firing pattern (Persinger, 1999).
  • My study on enhanced hypnotic suggestibility (Persinger, 1996).
  • A study that assessed the pleasantness of a long-term potentiation signal (Persinger, 1994).
  • A study of coherent responses to Reiki between practitioners and clients (Ventura, 2014)
  • An experiment with altered state experiences with circumcerebral magnetic stimulation (Collins, 2013)
  • Lowering depression and increasing alpha activity in the frontal lobe. (Corradini, 2013)

Sham fields are also used in our studies with cell cultures (Murugan, 2014 A), water Ph (Murigan, 2014 B), Obesity in rats (St-Pierre, 2014), Suppression of Cancer cells, (Karbowski, 2012), energy storage in water (Gang, 2012), planeria studies (Gang, 2011)  and scores of other studies that didn’t use human subjects.

The issue of double blind and placebo control is less important with our modern technology because of the availability of normative (“averages”) for different states, including placebo response states.  Comparing the results of our EEG studies to standard normative EEG states allows us to make inferences that would have required baseline (control) readings just a few years ago (Congedo, 2010).

During the last 5 years, quantitative electroencephalographic measurements by computer and the algorithms to compute distributions of power within the volume of the brain for different frequency bands have become available, and these have revealed that different patterns of fields, delivered to different sides of the brain, produce specific patterns regardless if the person knows if a field is presented or not (Saroka, 2013). Placebo effects produce very specific patterns that are not the same as those associated with either the field presentation or the field plus sensed presence effect.

In spite of claims to the contrary, we do use placebo controls and blind experimental conditions.  Our emphasis has been on quantifiable data, replication, and blind conditions, wherever possible and appropriate.  We remain committed to the scientific method.

I hope this blog will clarify our use of blind conditions, placebo controls and suggestion in our laboratory.

Dr. Michael A. Persinger
Full Professor
Behavioural Neuroscience, Biomolecular Sciences and Human Studies
Departments of Psychology and Biology
Laurentian University,
Sudbury, Ontario, Canada P3E 2C6
Email: mpersinger@laurentian.ca and drpersinger@neurocog.ca
NOTE: This blog is hosted by a colleague.

P.M. Richards, S.A. Koren, M.A. Persinger, Experimental stimulation by burst-firing weak magnetic fields over the right temporal lobe may facilitate apprehension in women, Perceptual and Motor Skills 75 (1992) 667–670.

Persinger MA, Richards PM, Koren SA.  “Differential ratings of pleasantness following right and left hemispheric application of low energy magnetic fields that stimulate long-term potentiation.”  International Journal of Neuroscience. 1994 Dec;79(3-4):191-7.

Healey F, Persinger MA, Koren SA.  “Enhanced hypnotic suggestibility following application of burst-firing magnetic fields over the right temporoparietal lobes: a replication.”  International Journal of Neuroscience.  1996 Nov;87(3-4):201-7.

Krippner, Stanley, and Persinger, Michael. “Evidence for enhanced congruence between dreams and distant target material during periods of decreased geomagnetic activity.” Journal of Scientific Exploration 10.4 (1996): 487-493.

Persinger, M. A. “Increased emergence of alpha activity over the left but not the right temporal lobe within a dark acoustic chamber: differential response of the left but not the right hemisphere to transcerebral magnetic fields.” International Journal of Psychophysiology 34.2 (1999): 163-169.

M.A. Persinger, F. Healey, Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields, Journal of . Nervous and Mental Disorders. 190 (2002) 533–541.

Booth, J. N., S. A. Koren, and M. A. Persinger. “Increased feelings of the sensed presence and increased geomagnetic activity at the time of the experience during exposures to transcerebral weak complex magnetic fields.”International Journal of Neuroscience 115.7 (2005 A): 1053-1079.

Tiller, S.G; Persinger, M.A. , Geophysical variables and behavior: XCVII. Increased proportions of left-sided sense of presence induced experimentally by right hemispheric application of specific (frequency-modulated) complex magnetic fields, Perceptual and Motor Skills 94 (2002) 26–28.

Persinger, Michael A., Letter to the Editor “A response to Granqvist et al. “Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak magnetic fields” Neuroscience Letters 380 (2005) 346–347

Makarec, Katherine,; Persinger, Michael A. “Electroencephalographic Validation of a Temporal Lobe Signs Inventory in a Normal Population”, Journal of Research in Personality, 24, 323-337 (1990)

Corradini, Paula L. Collins, Mark W. G.  Persinger Dr. Michael A.  “Facilitation of Declarative Memory and Congruent Brain States by Applications of Weak, Patterned Magnetic Fields: The Future of Memory Access?”  International Journal of Humanities and Social Science Vol. 4, No. 13; November 2014, 30

Neil M. Fournier, Quoc Hao Mach, Paul D. Whissell, Michael A. Persinger “Neurodevelopmental anomalies of the hippocampus in rats exposed to weak intensity complex magnetic fields throughout gestation” International Journal of Developmental Neuroscience 30 (2012) 427–433

Whissell, P.D. , Persinger, M.A.; “Developmental effects of perinatal exposure to extremely weak 7 Hz magnetic fields and nitric oxide modulation in the Wistar albino rat ” International Journal of Developmental Neuroscience 25 (2007) 433–439

McKay, B. E., and M. A. Persinger. “Normal spatial and contextual learning for ketamine-treated rats in the pilocarpine epilepsy model.” Pharmacology Biochemistry and Behavior 78.1 (2004): 111-119.

Bureau, Y. R. J., O. Peredery, and M. A. Persinger. “Concordance of quantitative damage within the diencephalon and telencephalon following systemic pilocarpine (380 mg/kg) or lithium (3 mEq/kg)/pilocarpine (30 mg/kg) induced seizures.” Brain Research 648.2 (1994): 265-269.

Missaghi, Babik, Pauline M. Richards, and Michael A. Persinger. “Severity of experimental allergic encephalomyelitis in rats depends upon the temporal contiguity between limbic seizures and inoculation.” Pharmacology Biochemistry and Behavior 43.4 (1992): 1081-1086.

Cook, Lisa L., and M. A. Persinger. “Infiltration of lymphocytes in the limbic brain following stimulation of subclinical cellular immunity and low dosages of lithium and a cholinergic agent.” Toxicology letters 109.1 (1999): 77-85.

Mulligan, Bryce P. , Noa Gang, Glenn H. Parker, Michael A. Persinger  “Magnetic Field Intensity/Melatonin-Molarity Interactions: Experimental Support with Planarian (Dugesia sp.) Activity for a Resonance-Like Process” Open Journal of Biophysics, 2012, 2, 137-143

Hunter, M.D., Mulligan, B.P., Dotta, B. T., Saroka, K. S., Lavallee, C. F., Koren, S. A., & Persinger, M. A., “Cerebral Dynamics and Discrete Energy Changes in the Personal Physical Environment During Intuitive-Like States and Perceptions” Journal of Consciousness Exploration & Research December 2010, Vol. 1, Issue 9, pp. 1179-1197

Persinger MA, Roll WG, Tiller SG, Koren SA, Cook CM.  “Remote viewing with the artist Ingo Swann: neuropsychological profile, electroencephalographic correlates, magnetic resonance imaging (MRI), and possible mechanisms.”  Perceptual and Motor Skills.  2002(B) Jun;94(3 Pt 1):927-49.

Murugan, Nirosha J., Lukasz M. Karbowski, and Michael A. Persinger. “Weak burst-firing magnetic fields that produce analgesia equivalent to morphine do not initiate activation of proliferation pathways in human breast cells in culture.” (2014).

Murugan, N. J., L. M. Karbowski, and M. A. Persinger. “Serial pH Increments (~ 20 to 40 Milliseconds) in Water during Exposures to Weak, Physiologically Patterned Magnetic Fields: Implications for Consciousness.” Water 6 (2014): 45-60.

St-Pierre, Linda S., and Michael A. Persinger. “Progressive Obesity in Female Rats from Synergistic Interactions between Drugs and Whole Body Application of Weak, Physiologically Patterned Magnetic Fields.” Journal of Behavioral and Brain Science 2014

Ventura, Anabela C., Kevin S. Saroka, and Michael A. Persinger. “Non-Locality changes in intercerebral theta band coherence between practitioners and subjects during distant Reiki procedures.” Journal of Nonlocality 3.1 (2014).

Collins, Mark W. G. Persinger, Michael A.  “Changing Velocity Circumcerebral Magnetic Fields Produce Altered State Experiences and Lowered Delta-Theta Power over the Temporal Lobes”  Frontiers in Psychological and Behavioral Science Apr. 2013, Vol. 2 Iss. 2, PP. 26-29

Corradini, Paula L., and Michael A. Persinger. “Brief Cerebral Applications of Weak, Physiologically-patterned Magnetic Fields Decrease Psychometric Depression and Increase Frontal Beta Activity in Normal Subjects.” Journal of Neurology & Neurophysiology (2013).

Karbowski, Lukasz M., et al. “Digitized quantitative electroencephalographic patterns applied as magnetic fields inhibit melanoma cell proliferation in culture.” Neuroscience letters 523.2 (2012): 131-134.

Gang, N., L. S. St-Pierre, and M. A. Persinger. “Water dynamics following treatment by one hour 0.16 Tesla static magnetic fields depend on exposure volume.” Water 3 (2012): 122-131.

Gang, Noa, and Michael A. Persinger. “Planarian activity differences when maintained in water pre-treated with magnetic fields: a nonlinear effect.”Electromagnetic biology and medicine 30.4 (2011): 198-204.

Congedo, Marco, et al. “Group independent component analysis of resting state EEG in large normative samples.” International Journal of Psychophysiology78.2 (2010): 89-99.

Saroka, Kevin & Persinger MA, “Potential production of Hughlings Jackson’s “parasitic consciousness” by physiologically patterned weak transcerebral magnetic fields: QEEG and source localization” Epilepsy and Behavior, 2013, 28, 395-407


Olaf Blanke’s Robot Ghost & “Artificial Spirit” – God Helmet findings corroborated.

Some of Dr. Michael Persinger’s “God Helmet results were corroborated when Dr. Olaf Blanke did an experiment in which he elicited the sensation of an apparition in his lab.  He did this by using a machine designed to reproduce a subjects own movements, placed behind their backs.  It worked by pressing the subjects from the back as they pressed forward with a finger-controlled joystick. His experiment, published HERE, is called:

Neurological and Robot-Controlled Induction of an Apparition

Dr M.A. Persinger has been studying this phenomenon for decades, under  the name of the “Sensed Presence”  (Dr Blanke calls it the FoP, or “Feeling of Presence”), and his research lends weight to Blanke’s recent work.

Some journalists are under the impression that Blanke (et al.) are the first to create an artificial ghostly experience.  In fact, Dr. Persinger, of Laurentian University’s Neuroscience Research group, did the same thing 14 years ago in an oft-cited case history:    link


Before Blanke’s experiment, Dr. M. A. Persinger had done many studies on laboratory-elicited sensed presences, and published a couple of articles laying out his ideas about why it happens. A search at pubmed.com showed 25 results for the search string persinger sensed presence -and that’s only the ones that mention it in the summary or abstract.  There are others (about 15 more) that discuss it in the body of the papers.

Persinger’s God Helmet has recently had some new and independent corroboration from researchers in Brazil (showing that its effects are not due to suggestibility).  Blanke’s paper confirms other aspects of Persinger’s findings, this time that the sense of a presence has its origins in the human brain, and can be explained as an alteration in the sense of self.  Persinger and Blanke agree that when people are feeling the sense of a presence (or feeling of presence) they’re actually perceiving a part of themselves.   Both Persinger and Blanke agree that the temporo-parietal region plays a role, though they may not agree on whether or not it plays the central role.  They emphasize different places in the brain, but this may only reflect their different research methods.

Persinger used neural stimulation with magnetic fields to create the sensed presence feeling, while Blanke (et al.) used a robot.  Persinger was the first to elicit this sensation using magnetic brain stimulation, while Blanke is the first to create it using a robot.  However, one of the 14 authors of the Blanke (et al.) paper seems to have made a mistake, erroneously saying “the FoP (feeling of presence – author) has never before been induced experimentally”.  Dr. M.A. Persinger has done just that (sample of this work here), but he used a different name (“sensed presence” instead of “feeling of presence”).  Blanke spoke about this in a filmed interview with the Washington Post, where he said he was to first to elicit this sensation using a robot.  Typos and copy-editing errors happen in scientific papers, just like any other kind of writing.


Here are the three brain regions Blanke and his colleagues found associated with feeling a presence, and Persinger’s papers corroborate all of them:
1) The temporoparietal cortex (in five of Blanke’s patients)
2) The frontoparietal cortex (in five of Blanke’s patients)
3) The insula (in five of Blanke’s patients).

The Temporoparietal Cortex

The temporoparietal cortex, the first area, is the location for the magnetic coils (“solenoids”). This is the area on the surface of the brain most clearly involved in the feeling of a presence in Persinger’s  “God Helmet” experiments, where one way of applying his magnetic signals elicited the sense of a presence in 80% of his subjects. Persinger’s research also implicates some areas in the limbic system, deep in the brain.

Some commentators have claimed that Persinger’s published effects are due to suggestibility, but this has been ruled out by a recent study that replicated some of Persinger’s work.

The Frontoparietal Area

Blanke wrote that his research especially associated the frontoparietal area with the feeling of a presence.

Persinger noted the frontoparietal cortex’s involvement in the Sensed Presence experience in a paper published in 2008.

The sensed presence (the feeling of another entity other than the self) … has been associated with altered perfusion within the frontoparietal regions”  link (to abstract only)

The frontoparietal regions have also been observed to participate in “speaking in tongues“, as Persinger noted in a 2009 paper.

Blanke (et al.) noted that  patients who had Feeling of Presence experiences most also “had significantly larger lesions in Brodmann’s area 7.”


It could be argued that Brodmann’s area 7 is not in the frontoparietal area, but rather in the parietal lobes, (toward the back of the brain), but naming conventions in brain science aren’t always consistent.


The insula has been known to contribute to sensed presence experiences, as one published case shows.  Persinger recorded “enhanced activity extending into the insula” when he took EEG recordings from Sean Harribance, the remote viewer, while the subject was “calling an angel”.  This feeling of an angelic presence was part of his psychic practices.  Of course, Angels and Ghosts are both taken as correlating with brain activity, and there is evidence that the insula is involved, as both Blanke’s and Persinger’s work demonstrate.

Deciding which brain regions ’cause’ a feeling or sensation is always difficult.  Here’s a metaphor:  A television is controlled by the on/off button.  At first glance, the remote control might seem to cause the images to appear.  However, the power button could also be said to be the cause, especially when you press it, right?  In fact, they’re both part of a single circuit that controls the whole television, including the images, the volume, the contrast and the brightness, and so forth.  So it may be with feeling the sense of a presence.  Persinger and Blanke’s two very different methods might provide two different points of entry to the same circuit.

I wrote to Dr. Persinger about Blanke’s experiment, and this was part of his reply (Nov. 10th, 2014):

“… the only difference between what Blanke is doing and what we have done is that he stimulates at the periphery to initiate the pathways that produce the experience while we are more likely directly stimulating the areas of the brain that receive that stimuli.”

In simpler terms, Blanke’s experiment elicited the sense of a presence from the outside in, and Persinger created it stimulating it from the inside out.


When Blanke and his colleagues had their robot touch their subject’s back at the same time they moved their fingertip-joystick, so they felt they were touching their own back.  When Blanke introduced a 500 msec delay (so the robot waited half a second before passing on the motion to the subject), the subjects began to feel that they were being touched by a ghost, or another person.  The illusion was so powerful that some subjects felt there were several people (up to four) standing behind them.  Two of the subjects felt uncomfortable enough to ask to stop the experiment.

It may seem that there’s no connection between the FoP Blanke’s group created (by poking their subjects in the back with a robot arm, directed by a time-delayed control stick) and the sense of a presence in other contexts, but Blanke included a simple test that strongly implies they are made of the same “stuff”.  While his subjects were being gently prodded by the robot and feeling it was a ghost, he asked them how many people they ‘felt’ were in the room next door.  The ones who were asked this question while they were feeling a presence also ‘felt’ there were more people in the next room.  The difference was about 20%.

Persinger has also elicited multiple presences, as you can see in this YouTube video (cued to the point where the subject describes feeling several presences):


Persinger’s God Helmet uses four magnetic coils over each side of their heads, but only one is activated at a time.  They take turns producing the magnetic field, changing (you guessed it!) every 500 msec.  The time lag that made the subjects feel they were being touched by a non-existent person (or ghost) is also the same time lag that Persinger found made the sensed presence most likely, when it was used to ‘time’ the cycle for his magnetic coils.

Persinger & Blanke had differing results, but certainly not conflicting ones.  Instead, Persinger and Blanke’s findings confirm and partly replicate each other.  The differences in their experimental techniques can account for the differences in their findings.

Persinger & Blanke both report vestibular effects from their experiments.  This refers to sensations where people feel they are moving when they’re not.  Vertigo is one example of a vestibular sensation.  Persinger has elicited vestibular effects from his God Helmet, and in one case, found that women were more likely to report them than men.  Blanke found that when subjects felt a presence, they also felt like they were drifting backwards.  Persinger found that these sensations precede the sensed presence in some circumstances.

What Causes the Feeling of a Presence?

Blanke wrote:  “… the FoP is caused by focal brain lesions.”  My opinion is different.  I certainly agree that some feelings of a presence are caused by lesions, but I’m also convinced that there is an evolutionary basis for this sensation.  It’s more likely in times of stress, especially during or just after potentially lethal situations.  In our early evolutionary history, stressful times were also times when we had a problem – and we needed a solution.  We could say the sensed presence can help us ‘think outside the box’ when we really need to – when we’re faced with a threat.   It offers us a way to achieve new insights – one that works outside our usual cognitive habits.

To understand this, we need to look at Persinger’s theory about what’s happening in moments when we sense people who aren’t there.  In Persinger’s view, we have two senses of self – one on each side of the brain.  Ordinarily, they work together seamlessly, giving us a unified feeling; a single but subtle feeling, that we exist – as one being.   Most of the time, we exist in the self on the left side of the brain, with its greater access to the language centers.  That’s why we’re such a verbal species.  Our minds keep coming up with words even when we’re alone (“mind chatter”).  Many people even talk to themselves  -out loud – if they’re alone too long.  We talk to others; its our main way of relating with them, and we often feel uncomfortable being with someone in silence.  Language is a part of our “selves”.

The “self” on the right side of the brain is subordinate most of the time.  It works in the shadow cast by the “linguistic self” on the left side, to use a metaphor.  It contributes ‘felt’ aspects of our thoughts, speech, body language and so forth.  Because is knows things without words, it knows in non-linear ways (has an “associative cognitive style”).  It takes a lot from the memory retrieval and creation pathways at work in the right side of the brain (in the hippocampus and surrounding cortex), letting us see connections between things that affect us in more ways than our talkative ways of thinking could ever cope with.

When the two senses of self aren’t communicating they way they usually do, the self on the left can perceive its counterpart directly, but not through any of our usual senses.  Only one of us can occupy our body, or identified as the “first-person singular” (the ego), so the other, the right-hemispheric self is evicted.  It’s bothering its neighbor on the left.  Its encroaching on its property, and so it has to go.  Where does it go, and how is it perceived once its gotten its notice to clear the premises?  Its felt as a being or presence outside our body’s space.  The feeling of presence.

Blanke wrote “the present data reveal the fine balance between the distributed cortical brain mechanisms in humans that generate the experience of ‘‘self’’ and ‘‘other,’’ which, if distorted, give rise to the FoP.”  I agree completely.  It may be that Blanke’s access to this circuit was through the body (sensorimotor), while Persinger’s is through the mind (affective and cognitive), as both run through the brain.

The sense that another person is there when we’re alone is a “social” hallucination, just like smelling smoke when the air is clear is an olfactory hallucination.  A smell that isn’t there implies a mis-firing in the olfactory bulbs.  Deja vu implies a mis-matching between our perception of the present moment and our sense of that past.  The sensed presence is an alteration in our sense of self-and-other, but its one of the functions of that sense, and is not – not at all –  intrinsically pathological.

That sense, that there is another person, being, entity, or spirit standing behind you is the source for ghosts, “spirit familiars”, doppelgangers, angels, “The Muse”, both Gods & demons, and a host of other seemingly non-physical beings.  All of them are variations on the same theme.  Thus, God, including the God of our prayers, is a manifestation of our sense of self from the right side of the brain – the ‘self’ that thinks outside the box created by the left-brain’s sense of self.

Prayer is a deliberate attempt to create the sensed presence (or Feeling of Presence). Its practiced in all known cultures, and has been through all known history.   We are a species that prays.  Huge numbers of people (I don’t know of any study that ever counted them) feel the presence of the god they pray to when they’re in prayer.  When people pray about their troubles and difficulties, they’re appealing to God, but they’re (only? also?) accessing the creativity that only the right hemisphere can manage (suggested reading on this subject).   To put it a bit differently, it’s the left hemisphere’s way of trying to quiten itself down, so the  right hemisphere’s normally-subordinate, intuitive way of thinking (“cognitive style”) can come through.  My book has a chapter on prayer that takes this view.

Accessing non-verbal thought isn’t the only thing that feeling an illusory presence might do for us.   It might also be a mechanism that tells us to be vigilant, even when the warnings around us are so subtle that we “just have a feeling” or a “hunch” that something is amiss.  There are lots of soldiers who’re sure they owe their lives to having known they were in danger, but without knowing how they knew.  Carl Sagan mentioned (here) that it might operate in the:

“… fear of “monsters”that almost all babies manifest around the time they become toddlers. Many predators who are circumspect when a human adult is around would happily attack a toddler. Hyenas, wolves, and large cats are only a few of the predators that stalked early humans and their immediate ancestors. When the child begins to amble off on it’s own, it helps for it to know – in it’s marrow – that there are monsters out there. With such knowledge, it’s much more likely to come running home to the grown-ups at the slightest sign of danger. Any mild predisposition in this direction will be resoundingly amplified by selection.”

Many, probably most, of the people who feel the presence of a (putative) non-physical being don’t have brain lesions or brain disorders of any kind.  While its true that epilepsy can elicit the sense of a presence, much of the phenomena that epilepsy creates appear when a seizure recruits pathways that support it naturally.  There are pathways used to remember music, and when these pathways are caught in a seizure, the person will probably hear music while its happening.

The feeling of a presence is a natural function that can be triggered through epilepsy, but that doesn’t make it an epileptic phenomena, and can’t be explained only in terms of the lesions that provoke epileptic events.  Its the foundation for spiritual sentiments that widen our cognitive strategies and refine our behaviors.  Its part of our evolutionary heritage.  However, not all people are equally prone to either the sense of a presence, or the urge to pray.  According to Persinger’s normative data (based on questionnaires that asked about the sense of a presence, among other things), about 1/3 of the population won’t feel such presences (and probably not feel drawn to prayer), 1/3 will feel them once in a while, and 1/3 will feel them often.  Epileptics and mystics are both at the extreme end of this spectrum, but for very different reasons.

We also expect to find schizophrenics at the same high end of this spectrum.  The disturbances in their brains will also include some of the pathways that support our ability to invoke presences, a skill that makes our thinking even more skilled, helping us to be less killed.  The intense prayer experiences of our early shamans contributed to the survival of our early communities, and thus, our species.

As a final note, here are references for 27 papers on the Sensed Presence that Persinger published Prior to Blanke’s (et al.) fascinating experiment.  Each is linked to it’s abstract.


Michael A. Persinger, Kevin S. Saroka Comparable proportions of classes of experiences and intracerebral consequences for surgical stimulation and external application of weak magnetic field patterns: Implications for converging effects in complex partial seizures Epilepsy & Behavior Volume 27, Issue 1, Pages 220–224, April 2013

Kevin S. Saroka, Michael A. Persinger Potential production of Hughlings Jackson’s “parasitic consciousness” by physiologically-patterned weak transcerebral magnetic fields: QEEG and source localization Epilepsy & Behavior 27 (2013) 220–224


Roll WG, Saroka KS, Mulligan BP, Hunter MD, Dotta BT, Gang N, Scott MA, St-Pierre LS, Persinger MA.  Case report: a prototypical experience of ‘poltergeist’ activity, conspicuous quantitative electroencephalographic patterns, and sLORETA profiles – suggestions for intervention.   Neurocase. 2012;18(6):527-36


Booth JN, Persinger MA. Discrete shifts within the theta band between the frontal and parietal regions of the right hemisphere and the experiences of a sensed presence. Journal of Neuropsychiatry & Clinical Neuroscience. 2009 Summer;21(3):279-83.

Meli SC, Persinger MA.  Red light facilitates the sensed presence elicited by application of weak, burst-firing magnetic fields over the temporal lobes.  International Journal of Neuroscience. 2009;119(1):68-75.

Persinger MA, Tiller SG.  Case report: A prototypical spontaneous ‘sensed presence’ of a sentient being and concomitant electroencephalographic activity in the clinical laboratory.   Neurocase. 2008;14(5):425-30.

St-Pierre LS, Persinger MA.  Experimental facilitation of the sensed presence is predicted by the specific patterns of the applied magnetic fields, not by suggestibility: re-analyses of 19 experiments.   International Journal of Neuroscience. 2006 Sep;116(9):1079-96.

Booth JN, Koren SA, Persinger MA.   Increased feelings of the sensed presence and increased geomagnetic activity at the time of the experience during exposures to transcerebral weak complex magnetic fields.   International Journal of Neuroscience. 2005 Jul;115(7):1053-79.

Persinger MA, Koren SA.   A response to Granqvist et al. “Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak magnetic fields”.    Neuroscience Letters. 2005 Jun 3;380(3):346-7; author reply 348-50. Epub 2005 Apr 21.

Persinger MA.  The sensed presence within experimental settings: implications for the male and female concept of self.   Journal of Psychology. 2003 Jan;137(1):5-16.

Persinger MA, Healey F.  Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields.   Journal of Nervous and Mental Disorders. 2002 Aug;190(8):533-41.

Tiller SG, Persinger MA.   Geophysical variables and behavior: XCVII. Increased proportions of the left-sided sense of presence induced experimentally by right hemispheric application of specific (frequency-modulated) complex magnetic fields.   Perceptual & Motor Skills. 2002 Feb;94(1):26-8.

Suess LA, Persinger MA.   Geophysical variables and behavior: XCVI. “Experiences” attributed to Christ and Mary at Marmora, Ontario, Canada may have been consequences of environmental electromagnetic stimulation: implications for religious movements.   Perceptual & Motor Skills. 2001 Oct;93(2):435-50.

Persinger MA, Koren SA, O’Connor RP.   Geophysical variables and behavior: CIV. Power-frequency magnetic field transients (5 microtesla) and reports of haunt experiences within an electronically dense house.   Perceptual & Motor Skills. 2001 Jun;92(3 Pt 1):673-4.

Persinger MA.   Subjective improvement following treatment with carbamazepine (Tegretol) for a subpopulation of patients with traumatic brain injuries.   Perceptual & Motor Skills. 2000 Feb;90(1):37-40.

Cook CM, Persinger MA.   Experimental induction of the “sensed presence” in normal subjects and an exceptional subject.
Perceptual & Motor Skills. 1997 Oct;85(2):683-93.

Persinger MA.   Sense of a presence and suicidal ideation following traumatic brain injury: indications of right-hemispheric intrusions from neuropsychological profiles.   Psychological Reports 1994 Dec;75(3 Pt 1):1059-70.

Tiller SG, Persinger MA.   Elevated incidence of a sensed presence and sexual arousal during partial sensory deprivation and sensitivity to hypnosis: implications for hemisphericity and gender differences.   Perceptual & Motor Skills. 1994 Dec;79(3 Pt 2):1527-31.

Johnson CP, Persinger MA.   The sensed presence may be facilitated by interhemispheric intercalation: relative efficacy of the Mind’s Eye, Hemi-Sync Tape, and bilateral temporal magnetic field stimulation.  Perceptual & Motor Skills. 1994 Aug;79(1 Pt 1):351-4.

Persinger MA, Bureau YR, Peredery OP, Richards PM.   The sensed presence as right hemispheric intrusions into the left hemispheric awareness of self: an illustrative case study.   Perceptual & Motor Skills. 1994 Jun;78(3 Pt 1):999-1009.

Dittburner TL, Persinger MA.   Intensity of amnesia during hypnosis is positively correlated with estimated prevalence of sexual abuse and alien abductions: implications for the false memory syndrome.   Perceptual & Motor Skills. 1993 Dec;77(3 Pt 1):895-8.

Persinger MA.   Vectorial cerebral hemisphericity as differential sources for the sensed presence, mystical experiences and religious conversions.
Perceptual & Motor Skills. 1993 Jun;76(3 Pt 1):915-30. Review.

Persinger MA.   Transcendental Meditation and general meditation are associated with enhanced complex partial epileptic-like signs: evidence for “cognitive” kindling?
Perceptual & Motor Skills. 1993 Feb;76(1):80-2.

Persinger MA.   Paranormal and religious beliefs may be mediated differentially by subcortical and cortical phenomenological processes of the temporal (limbic) lobes.   Perceptual & Motor Skills. 1993 Feb;76(1):247-51.

Persinger MA.   Enhanced incidence of “the sensed presence” in people who have learned to meditate: support for the right hemispheric intrusion hypothesis.   Perceptual & Motor Skills. 1992 Dec;75(3 Pt 2):1308-10.

Munro C, Persinger MA.   Relative right temporal-lobe theta activity correlates with Vingiano’s hemispheric quotient and the “sensed presence”.   Perceptual & Motor Skills. 1992 Dec;75(3 Pt 1):899-903.

Lavallée MR, Persinger MA.   Left ear (right temporal lobe) suppressions during dichotic listening, ego-alien intrusion experiences and spiritualistic beliefs in normal women.   Perceptual & Motor Skills. 1992 Oct;75(2):547-51.